Electronic apparatus and hard disk drive housing apparatus

ABSTRACT

In hard disk drive (HDD) or an electronic apparatus in which the HDD is wrapped with a foam resin sheet and a metal outer casing to damp noise, heat radiation sheets for radiating far-infrared rays are attached to an inner casing of the HDD or to tops of the metal outer casing and a pair of far-infrared ray transmitting and receiving members composed of heat radiation sheets for absorbing far-infrared rays are attached to the inner surface of the metal outer casing or the inner surface of the cover of the electronic apparatus, which are located at spatially spaced apart positions. In this way accumulated heat in the HDD or the metal outer casing is radiated from the metal outer casing or the cover.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electronic apparatus and a hard diskdrive housing apparatus, and particularly to an electronic apparatus anda hard disk drive housing apparatus in which radiated heat and a noisefrom an electronic apparatus and a hard disk drive housing apparatus canbe absorbed so that the electronic apparatus and the hard disk drivehousing apparatus can be prevented from being affected by shock from theoutside.

2. Description of the Related Art

A known case main body for accommodating therein a drive unit rotatingat high speed within a hard disk drive (HDD) has had airtight propertyin order to prevent a noise generated when the drive unit is rotated andvibrated. From a heat radiation standpoint, such airtight case main bodyencounters with problems in which the above airtight case main body hasno convection of air, it accumulates heat and it cannot maintainsufficient heat radiation effect. To solve the above-mentioned problems,cited patent reference 1 has disclosed a HDD housing structure in whichtwo problems of heat radiation and absorption of vibration can be solvedeffectively while airtight property can be maintained.

FIG. 1 of the accompanying drawings is a schematic perspective viewshowing a HDD housing structure disclosed in the cited patent reference1.

As shown in FIG. 1, the above-described cited patent reference 1discloses a housing structure for housing a HDD 7 in which a hard diskdrive unit and the like are housed within a flat case 1 of which outwardappearance is substantially a rectangular solid and in which noiseabsorption members 4 a, 4 b, 4 c and 4 d are provided within the case 1.As shown in FIG. 1, the case 1 is composed of a case lid 2 and abox-like case main body 3 with the case 2 mounted to an open bottomportion thereof. Noise absorption members 4 a, 4 b, 4 c and 4 d, each ofwhich has a predetermined thickness, are disposed along the inner wallportion around the case main body 3. A heat radiation plate 5 is locatedon the inside of the top portion 3 a of the case main body 3 and a driveunit is located between supporting members 6L and 6R erected from theheat radiation plate 5 to the inside of the case main body 3. In orderto enable the heat radiation plate 5, the supporting members 6L, 6R andthe case lid 2 to form a heat radiation structure which contacts withthe drive unit to radiate heat from the drive unit, the case lid 2, thecase main body 3, the heat radiation plate 5 and the supporting members6L, 6R are made of aluminum or aluminum alloy.

According to this arrangement, the noise absorption members 4 a, 4 b, 4c and 4 d can absorb a vibration noise and they can also decreaseleakage of a noise to the outside. In addition, the case lid 2, the casemain body 3, the heat radiation plate 5 and the supporting members 6L,6R are made of material having excellent heat transmission property andhence heat radiation effect of the drive unit can be exhibited.

As shown in FIG. 1, the noise absorption members 4 a, 4 b, 4 c and 4 dare made of a sponge-like soft synthetic resin or a natural rubber and apart of the noise absorption members 4 a, 4 b, 4 c and 4 d can kept itsposition in the state in which it is held between the inner wall surfaceof the case main body 3 and the supporting members 6L, 6R. Also, theheat radiation plate 5 is attached to the inner surface of the case lid2 through a member with high heat transmission property and cushionproperty, for example, a square plate member 8 made of an adhesivesynthetic resin commercially available under the trade name of“SORBOTHANE” and this heat radiation plate 5 is brought in contact withthe drive unit of the HDD 7. A second heat radiation plate 5 a isprovided between the case lid 2 and the heat radiation plate 5 and it isbrought in contact with the case lid 2 through the second square member8 a and the noise absorption member 4 d. Accordingly, heat istransmitted from the heat radiation plate 5 a to the case lid 2 by thesecond square plate member 8 a with the high heat transmission propertyand the cushion property.

Further, a cited patent reference 2 has disclosed a structure tocompletely house a hard disk (HD) into a box made of a noise absorptionmaterial 4 as an attachment structure in which a noise generated fromthe HDD 7 can be decreased and in which heat radiation efficiency can beimproved.

FIG. 2 is a cross-sectional side view showing the HDD 7 disclosed as anexample of the related art of the cited patent reference 2. Thisrelated-art example has a silent disk drive structure that has beendescribed in the specification of U.S. Pat. No. 5,510,954. Therelated-art example is composed of the noise absorption member 4provided in the periphery of the HDD 7, a noise insulation case 15provided in a heat sink 9 and a heat transmission path 10.

Specifically, as shown in FIG. 2, a disk drive 11 of the HDD 7 isenclosed by a heat transmission and vibration absorption member 12 and ametal case 13 of the HDD 7. The noise absorption member 4 is providedbetween the metal case 13 and the noise insulation case 15 and the metalcase 13 and the heat sink 9 is connected by the heat transmission path10.

According to the arrangement of the HDD 7 described in theabove-mentioned cited patent reference 1, the noise absorption members 4a to 4 d and the two heat radiation plates 3 and 3 a are housed withinthe case main body 3 and the case lid 2 comprising the case 1 and therearises a problem, in which the case 1 of the HDD 7 becomes large insize.

Also, according to the arrangement of the HDD 7 described in theabove-mentioned cited patent reference 2, the following problems arisein addition to the problem encountered with the above-mentioned citedpatent reference 1.

Since the HDD 7 containing the HD (disk drive 11) generates a largeamount of heat and it should be kept under a certain circumstancetemperature in order to maintain function reliability, when the HDD 7 iscompletely housed within the box of the noise insulation case 15 coveredwith the noise absorption member 4, heat radiation effect becomes aserious problem depending upon the surrounding air circumstanceconditions. Although heat is radiated by the heat sink 9 located outsidethe noise insulation case 15 through the heat transmission path 10 inthe cited patent reference 2, in the case of the HDD which generates alarge amount of heat, there is a limit to generate heat by using onlythe heat sink 9 and hence it becomes difficult to keep the HD within theHDD 7 and the head under a constant circumstance temperature.

Also, in order to increase heat radiation efficiency, the heat sink 9should become large in size and hence the space is increased, whichmakes the whole of the HDD 7 become larger in size. When external forcesuch as shock is applied to such heat sink 9 from the outside, the diskdrive of the HDD 7 is directly vibrated and problems arise, in which thepickup head and the like will be broken.

Further, as a condition under which the HDD 7 is mounted on theelectronic apparatus, there is prescribed that the HDD 7 should bemounted with a constant distance from other components to be mounted.The reason for this is that an atmospheric pressure within the metalcase 13 of the HDD 7 should be kept constant and breathing holes shouldbe closed so that stress may not be applied to the HD. In thearrangement shown in FIG. 2, since the heat transmission path 10directly comes in contact with the HDD 7, a problem arises, in whichfunction reliability of the disk drive 11 will be affected.

-   -   [Cited patent reference 1]: Official gazette of Japanese        laid-open patent application No. 2002-74929    -   [Cited patent reference 2]: Official gazette of Japanese        laid-open patent application No. 11-66832

SUMMARY OF THE INVENTION

In view of the aforesaid aspect, it is an object of the presentinvention to provide an electronic apparatus and a HDD in which the HDDcan be protected from shock when the electronic apparatus and a heatradiation device of the HDD are shocked from the outside.

It is another object of the present invention to provide an electronicapparatus and a HDD in which heat generated from the HDD can be radiatedefficiently and in which highly-reliable hard disk function can bemaintained by decreasing a seek noise generated when a pickup headwithin the HDD frequently seeks a target track.

According to an aspect of the present invention, there is provided anelectronic apparatus which is comprised of a hard disk drive forrecording and/or reproducing a signal, a heat transmission portion forreceiving heat generated from the hard disk drive and transmittingreceived heat, a heat radiation portion for radiating transmitted heatand an arrangement in which the hard disk drive is attached to a fixedportion of the electronic apparatus through an elastic material, theheat radiation portion is attached to the fixed portion of theelectronic apparatus without the elastic material and heat istransmitted to the hard disk drive, the heat radiation portion and theheat transmission portion through two opposing surfaces of far-infraredray transmitting and receiving member distant from each other by apredetermined distance.

According to other aspect of the present invention, in theabove-mentioned electronic apparatus, the electronic apparatus iscomprised of a box type outer casing in which an inner casing of thehard disk drive is housed through a noise insulation member or avibration isolation member, a chassis for holding the outer casing by ashock-absorbing member and a cover for covering the chassis, whereinheat from the inner casing of the hard disk drive is transmitted to theouter casing and the thus transmitted heat is radiated through thefar-infrared ray transmitting and receiving member disposed on the outersurface of the outer casing to the cover with or without thefar-infrared ray transmitting and receiving member being disposed.

In accordance with a further aspect of the present invention, there isprovided a hard disk drive housing apparatus which is comprised of a boxtype outer casing in which a hard disk drive is housed through a noiseinsulation member or a vibration isolation member, a chassis for holdingthe outer casing by a shock-absorbing member, a cover for covering thechassis, a heat transmission portion disposed on a top of the innercasing of the hard disk drive housing apparatus. The hard disk drivehousing apparatus further comprises a far-infrared ray transmitting andreceiving member disposed on the outer surface of the outer casing and aheat radiation portion with or without the far-infrared ray transmittingand receiving member disposed at the position opposing to and spacedapart from the outer surface of the outer casing, wherein heat of theinner casing is transmitted to the outer casing through the heattransmission portion and heat within the inner casing is radiated to theheat radiation portion.

According to the above-mentioned HDD and electronic apparatus of thepresent invention, there can be obtained the HDD and the electronicapparatus in which the HDD can be protected from being shocked when theshock is applied the electronic apparatus and the heat radiation meansof the HDD from the outside.

According to the electronic apparatus and the HDD of the presentinvention, there can be obtained the electronic apparatus and the HDD inwhich heat generated from the HDD can be efficiently radiated and a seeknoise generated when the pickup head within the HDD frequently seeks atarget track can be decreased so that reliability of hard disk functioncan be maintained.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a hard disk drive (HDD) and towhich reference will be made in explaining a noise insulation unitaccording to the related art:

FIG. 2 is a cross-sectional side view of a hard disk drive shown in anexample of the related art and to which reference will be made inexplaining a noise insulation unit according to the related art;

FIG. 3 is a perspective view showing an overall arrangement of arecorder according to an embodiment of the present invention with itscover being removed;

FIG. 4 is a plan view showing a chassis of the recorder shown in FIG. 3;

FIG. 5 is a perspective view showing the chassis of the recorderaccording to the present invention and to which reference will be madein explaining the state in which an air current is disturbed by coolingfans;

FIG. 6 is a plan view of the HDD and shows schematically the layout ofthe cooling fans for use with the recorder according to the presentinvention;

FIG. 7 is a perspective view of an outward appearance showing theattached state of a HDD drive unit for use with the recorder accordingto the present invention;

FIG. 8 is a cross-sectional view taken along the line VIII-VIII in FIG.7 and to which reference will be made in explaining a heat radiationmethod in the HDD for use with the recorder according to the presentinvention;

FIG. 9 is an exploded perspective view showing the state in which theHDD for use with the recorder according to the present invention isattached to an outer casing;

FIG. 10 is a perspective view showing a film sheet for use with therecorder according to the present invention;

FIG. 11 is a perspective view showing the state in which an elasticmember and an earth ground member are attached to the film sheet of FIG.10;

FIGS. 12A and 12B are schematic diagrams showing the state in which theHDD is assembled on the outer casing for use with the recorder accordingto the present invention, respectively;

FIG. 12C is a schematic diagram showing a portion D in FIG. 12B in anenlarged-scale;

FIGS. 13A and 13B are perspective views used to explain a pull-outmember to pull out the HDD from the outer casing of the recorderaccording to the present invention, respectively;

FIG. 14 is a schematic cross-sectional side view used to explain thestate in which the HDD is pulled out of the outer casing of the recorderaccording to the present invention;

FIG. 15 is a flowchart to which reference will be made in explaining amethod for controlling a plurality of cooling fans according to thepresent invention;

FIGS. 16A and 16B are respectively cross-sectional side views similar toFIG. 8 and illustrate a main portion of another embodiment of thepresent invention and to which reference will be made in explaining amethod for radiating heat from the HDD according to the presentinvention; and

FIG. 17 is a perspective view similar to FIG. 10 and shows a film sheetfor use with the recorder according to another embodiment of the presentinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

An electronic apparatus and a hard disk drive (HDD) according to anembodiment of the present invention will hereinafter be described withreference to FIGS. 3 to 15 on the basis of a recorder including aplurality of recording and/or reproducing drive units, by way ofexample.

FIG. 3 is a perspective view showing an overall arrangement of arecorder according to the present invention with its cover beingremoved; FIG. 4 is a plan view showing a chassis of the recorder; FIG. 5is a perspective view of the chassis of the recorder and to whichreference will be made in explaining the state in which air is sent byventilators; FIG. 6 is a schematic plan view used to explain the statein which air is sent by ventilators; FIG. 7 is a perspective view usedto explain the state in which a HDD is attached to a HDD drive unit ofthe recorder: FIG. 8 is a cross-sectional view taken along the lineVIII-VIII in FIG. 7; FIG. 9 is an exploded perspective view showing thestate in which the HDD is attached to the outer casing; FIG. 10 is aperspective view showing a film sheet; FIG. 11 is a perspective viewshowing the state in which an elastic member and an earth ground memberare attached to the film sheet; FIGS. 12A, 12B and 12C are schematicdiagrams used to explain the state in which the HDD is assembled to theouter casing, respectively; FIGS. 13A, 13B and FIG. 14 are schematicperspective views and a schematic cross-sectional side view used toexplain the state in which the HDD is pulled out of the outer casing,respectively; and FIG. 15 is a flowchart to which reference will be madein explaining a method of controlling a plurality of cooling fansaccording to the present invention.

As shown in FIG. 3, a recorder 20 used as an electronic apparatusincludes a main casing 25 composed of a chassis 21 having asubstantially U-like cross-section made of a suitable metal such asaluminum, a panel 22 and a back plate 23 disposed on the front side andthe back side of the chassis 21 and a cover (not shown in FIG. 3 butshown in FIG. 8) 24 having a substantially U-like cross-section.

The chassis 21 of the recorder 20 has vent holes bored thereon to takeair into the recorder 20. The chassis 21 has a ventilator 26 a (seeFIGS. 3 and 6) and ventilators 26 b, 26 c (see FIGS. 4 and 5) formedthereon, and a cover 24 also have suitable vent holes bored thereon. Apower supply unit 27 is disposed on the left front side of the majorsurface of the chassis 21, a DVD drive unit 28 is disposed on thecentral front side of the chassis 21 and a HDD drive unit 29 is disposedon the right front side of the major surface of the chassis 21. Apartition plate 30 is disposed at substantially the central position ofthe chassis 21 so as to become parallel to the panel 22 and the backplate 23. A tuner unit 31 is disposed at the right back side between thepartition plate 30 and the back plate 23 on the chassis 21. A computerunit (CPU (central processing unit)) 34 with heat radiation members suchas a second cooling fan 35 with a relatively small capacity and a heatsink 33 is disposed at the central back side in the state in which theyare inclined in the longitudinal direction of the partition plate 30. Afirst cooling fan 32 with a relatively large capacity is disposed on theleft-hand side of the back plate 23. The panel 22 has at least on itsfront formed a tray slot 37 of a size large enough to load and unload atray 36 which can be freely inserted into and ejected from the DVD driveunit 28. Although not shown, various kinds of operation devices aredisposed on the front of the panel 22.

As shown in a plan view of FIG. 4 and a perspective view of FIG. 5showing the chassis 21 with its panel 22 being removed, an open airdetection sensor 38 for detecting a temperature of the open air isprovided in the vicinity of the ventilator 26 c bored on the chassis 21of the front portion of the HDD drive unit 29. A CPU sensor 39 forcontrolling a temperature of the CPU 34 is located within the CPU 34. InFIG. 4, reference numerals 40 denote rubber leg members comprising shockabsorbing devices.

In the recorder 20 according to this embodiment, as shown in FIG. 5, theopen air 42 taken from the above-described respective ventilators 26 a,26 b and 26 c is absorbed by the second cooling fan 35 through openingholes 41 bored through the partition plate 30 so that the open air 42 isforcedly air-cooled behind the back plate 23 by the first cooling fan 32while the heat sink 33 of the CPU 34 is being air-cooled.

When the above-mentioned second cooling fan 35 is inclined with a properinclination angle relative to the opening holes 41 bored through thepartition plate 30, the air-cooling effect for air-cooling the heat sink33 of the CPU 34 can be enhanced. The reason for this will be describedwith reference to the schematic plan view of FIG. 6. In FIG. 6, elementsand parts identical to those of FIG. 5 are denoted by identicalreference numerals and therefore need not be described. FIG. 6 is a planview schematically showing the case in which the ventilation methodshown in FIG. 5 is applied to the inside of a substantially flatrectangular solid-like inner metal casing 43 comprising an enclosure ofa HDD 45 which will be described later on.

The open air 42 taken into the inner casing 43 from the ventilators 26a, 26 d bored through the left and right side walls of the inner casing43 and the ventilator 26 c bored through the front surface of the innercasing 43 is absorbed by the second cooling fan 35 and sent to the heatsink 33 located at the front surface of the second cooling fan 35 with aproper inclination angle. In the case of FIG. 6, the second cooling fan35 is not fixed to the chassis 21 with a proper inclination angle butthe heat sink 33 is inclined with a proper inclination angle relative tothe second cooling fan 35, which has a relative relationship with thecase of FIG. 5. Thus, it can be considered that the arrangement shown inFIG. 6 is identical to that shown in FIG. 5.

A heat generating device such as the CPU 34 is located under the heatsink 33. The first cooling fan 32 is attached to the back plate 23 ofthe inner casing 43 to exhaust the heated air from the inner casing 43through the first cooling fan 32 to the outside after the open air 42has passed through fins 44 of the heat sink 33 to cool the heatgenerating device such as the power supply unit 27. As described above,since a cool wind absorbed from the open air 42 sent from the secondcooling fan 35 enters into the fins 44 of the heat sink 33 with a properinclination angle, the fins 44 are cooled by a stronger cooling wind andhence a cooling effect for cooling the heat sink 33 can be enhanced.

The arrangement of the HDD drive unit 29 will be described next withreference to FIGS. 7 and 8. FIG. 8 is a cross-sectional view taken alongthe line VIII-VIII in FIG. 7. As illustrated, the HDD drive unit 29 isfixed to boss portions 46, formed by chassis contraction, on the chassis21 and a sub-chassis 47 fixed to the left side plate of the chassis 21bent in a U-like shape.

The sub-chassis 47 has a heat-radiation through-hole 48 of substantiallydome-like shape for exhausting air formed at substantially the centralportion of a substantially rectangular solid-like major surface 47thereof. Left and right ends of the major surface 47 are bent in theupper and lower direction so as to become perpendicular to each other toform an attachment leg portion 47 a and an attachment member 47 b. Theattachment leg portion 47 a is fixed to the chassis 21 through the bossportion 46, formed by chassis contraction, and the attachment member 47b is fixed to the right side surface portion of the chassis 21 which isbent in a U-like shape.

As shown in FIG. 8 which is a cross-sectional view taken along the lineVIII-VIII in FIG. 7, the HDD drive unit 29 is composed of a disk driveunit 51 covered with a metal box-like inner casing 50 serving as anenclosure, a pickup head 52, the HDD 45 including input and outputshroud groups (see FIG. 7) and the like, a shock-absorbing device (noiseabsorption member) in which the inner casing 50 of the HDD 45 isenclosed with a foam resin sheet 53 with cushion property such aspolyurethane, an elastic rubber and a foam soft synthetic resin to forma shock-absorbing and noise-insulation shock-absorbing device and anouter casing 54 serving as a noise insulation box.

The upper, lower, right and left plates and the back plate of the innercasing 50 of the HDD 45 are wrapped with the foam resin sheet 53 made ofpolyurethane for use in shock-absorbing and noise insulation and theinner casing 50 of the HDD 45 is further inserted into the noiseinsulation outer casing 54. A foam heat transmission sheet 55 isdisposed on the upper plate (top) of the inner casing 50. Morespecifically, the foam heat transmission sheet 55 for transmitting heataccumulated within the HDD 45 and which is transmitted to the top of theinner casing 50 is attached to the side of the outer casing 54 so as tobe brought in contact with a part of the top of the inner casing 50.

Further, electrically-conductive gaskets 56 made of a suitable materialsuch as a foam metal mesh for preventing the HDD 45 from being broken bystatic electricity are fixed to the outer casing 54 or they are fixed tothe left and right corner portions of the inner casing 50 of the HDD 45,thereby being electrically conducted with the inner casing 50 or theouter casing 54. In FIG. 8, reference numeral 57 denotes a thermoplasticor thermosetting film sheet having a slippery surface, such as apolyethylene or vinyl chloride thin film. A heat radiation sheet 66 afor radiating heat transmitted to the outer casing 54 is formed on theouter surface of the top 62 of the outer casing 54. Far-infrared raysradiated from this heat radiation film 66 a are radiated into a heatradiation sheet 66 b formed on the cover 24 of the recorder 20 locatedat the position spatially spaced apart from the top 62 of the outercasing 54. In this case, the heat radiation sheet 66 a radiates heat offar-infrared rays into the air and heat of the far-infrared raysradiated in the air is strongly absorbed by the same heat radiation heat66 b formed on the cover 24 of the recorder 20. Accordingly, heat fromthe inner casing 50 of the HDD 45 is radiated from the far-infrared rayheat radiation sheet 66 a attached to the outer casing 54 by thefar-infrared ray transmitting and receiving members composed of a pairof far-infrared ray heat radiation sheets 66 a and 66 b and absorbed bythe heat radiation sheet 66 b attached to the inner surface of the cover24. Heat raised at high temperature within the HDD 45 is radiated fromthe cover 24 comprising the heat radiation sheet portion. Although heatfrom the inner casing 50 can of course be radiated to the outside by thecover 24 without the heat radiation sheet 66 b formed on the side of thecover 24, when the heat radiation sheet 66 b is attached to the innersurface of the cover 24, heat radiated from the heat radiation sheet 66a can be efficiently absorbed by the heat radiation sheet 66 b andtherefore heat radiation effect can be enhanced.

A structure of the film sheet 57 for wrapping the inner casing 50 of theabove-mentioned HDD 45, a method for attaching the foam resin sheet 53and a method for mounting (inserting) the inner casing 50 wrapped withthe foam resin sheet 53 into the outer casing 54 will be described withreference to FIGS. 9, 10 and 11.

Prior to describing the present invention with reference to FIG. 9, thepresent invention will be described with reference to FIG. 10. FIG. 10is a perspective view showing an example of the film sheet 57. As shownin FIG. 10, the film sheet 57 made of a thin film synthetic resin suchas polyethylene and vinyl chloride and which has a slippery surface iscut in the form of a substantially rectangular solid. An upper sheet 57a which contacts with the top of the HDD 45 is composed of front, back,left and right folding sheet members 57F, 57B, 57L and 57R which arebrought in contact with the front, back, left and right plates of theHDD 45 and thereby folded along folding lines 57 h. A substantiallysquare-shaped lower sheet 57 b, continued from the folding sheet member57B to contact with the back side of the inner casing 50, has arectangular radiation opening 57 f formed thereon to radiate heat fromthe HDD 45. At the same time, the lower sheet 57 b has a tongue-likepull-out member 57 g punched out along the folding line 57 h.

The upper sheet 57 a has a square electrically conductive through-hole57 e formed at substantially the central position thereof and, asubstantially square heat transmission sheet 55 attached to the innersurface of the outer casing 54 is brought in contact with the top of theinner casing 50 through this electrically-conductive through-hole 57 e.Also, the upper sheet 57 a has front, back, right and left rectangularground through-holes 57 c, 57 d formed on the front, back, right andleft portions thereof. Four substantially square electrically-conductivegaskets 56 attached to the inner surface of the outer casing 54 arebrought in contact with the top of the inner casing 50 through theground through-holes 57 c, 57 d. That is, the film sheet 57 for use withthe present invention may be cut in the shape which results from addinga cross-like shape portion having left, right, front and back foldingareas and a rectangular shape from the original of the film sheet.

A method of attaching the foam resin sheet 53 to the film sheet 57 willbe described with reference to FIG. 11. As shown in FIG. 11, thesubstantially rectangular foam resin sheet 53 a is attached to the filmsheet 57 from the back side of the lower sheet 57 b. The foam resinsheets 53 b of similar shape are attached to the left and right foldingsheet members 57L, 57R, and further substantially L-like foam resinsheets 53 c and which have recesses corresponding to the rectangularground holes 57 c, 57 d are attached to the upper sheet 57 a. The L-likeshort side portion of one foam resin sheet 53 c is attached to the frontsheet folding member 57F and the long side portion thereof is attachedto the left side surface of the upper sheet 57 a. The L-like short sideportion of the other foam resin sheet 53 d is attached to the back sheetfolding member 57B and the long side portion thereof is attached to theright side surface of the upper sheet 57 a.

FIG. 9 is an exploded perspective view used to explain the assembledstate presented when the HDD 45 is mounted on the outer casing 54 of theHDD drive unit 29. A method of mounting the HDD 45 wrapped with thewrapping body 59 in which the foam resin sheet 53 is attached to thefilm sheet 57 from the back side of the outer casing 54 onto the outercasing 54 will be described below. The top 60 of the box-like enclosurecomprising the inner casing 50 of the HDD 45 is provided in the lowerside in FIG. 9 and the upper side of the top 60 is not provided with ametal bottom plate so that a printed circuit board and the like are madeopen. The disk drive unit 51, the pickup head 52 and the like aredisposed in the inside of the HDD 45 as has been described before indetail with reference to FIG. 8. In FIG. 9, reference numeral 49 denotesinput and output connection shroud group of the HDD 45.

The foam resin sheets 53 a, 53 b, 53 c and 53 d are attached to the filmsheet 57, described with reference to FIG. 10, to thereby form thewrapping body 59. The top 60 of the HDD 45 is mounted on the foam resinsheets 53 c and 53 d of the upper sheet 57 a of the film sheet 57comprising this wrapping body 59. Left, right, front and back foldingmembers 57L, 57R, 57F and 57B are folded so that they may be erected,respectively. The left, right, front and back side plates of the innercasing 50 of the HDD 45 are wrapped with the elastic foam resin sheets53 b, 53 c and 53 d which are excellent in vibration isolation propertyand noise insulation property and the lower sheet 57 b is mounted on theback side of the HDD 45, whereby the back side of the HDD 45 is coveredwith the foam resin sheet 53 a through the film sheet 57.

The HDD 45 wrapped with the wrapping body 59 in this manner is insertedinto the outer casing 54. As shown in FIG. 9, the outer casing 54 issubstantially a box made of a metal plate such as an aluminum plate.Left and right side plates 54L, 54R and the end portion of the back sideplate 54B of the outer casing 54 are bent in the direction perpendicularto the top 62 to thereby form a fixed hole 61 to fix the outer casing 54to the sub-chassis 47. Also, the front side plate 54F of the outercasing 54 is bent slightly so as to expose the connection shroud group49 of the HDD 45 to the outside. An elastic heat conductive sheet 55 ofa substantially rectangular shape with excellent heat conductionproperty and of which size is smaller than the rectangularelectrically-conductive hole 57 e bored on the film sheet 57 is bondedto the central position of the inside of the top 62 of the outer casing54. A non-silicon-based hyper soft heat radiation material (No. 5505S)manufactured by 3M CORPORATION, for example, can be used as this heatconductive sheet 55. This hyper soft heat radiation material is made ofa thin base film on which a heat conductive acrylic elastomer is formed.

The elastic electrically-conductive gaskets 56 of substantiallyrectangular shape with excellent electrically-conductive property andwhich are smaller than the rectangular ground holes 57 d, 57 c bored onthe film sheet 57 are bonded to left, right, front and back positions ofthe inside of the top 62 of the outer casing 54. A soft high seal gasket(SHSG) manufactured by KITAGAWA INDUSTRIES CO., LTD., for example, canbe used as this electrically-conductive gasket 56. This SHSG is made ofa foam resin with an electrically-conductive mesh mixed thereto and isable to keep electrically-conductive property under relatively lowcompression force.

An insertion method required when the sub-assembly wrapping body 65 inthe sub-assembly state in which the above-mentioned HDD 45 is wrappedwith the wrapping body 59 is inserted into the outer casing 54 will bedescribed with reference to FIGS. 12A, 12B and 12C. FIG. 12B is across-sectional side view showing the state in which the sub-assemblywrapping body 65 is cut along the direction perpendicular to the longside of the outer casing 54. A short side inside dimension L2, a longside inside dimension (not shown) and an inside height H2 of the outercasing 54 are smaller than a short side outer dimension L1, a long sideouter dimension (not shown) and an outside height H1 of the sub-assemblywrapping body 65. The reason for this is that the volume of thesub-assembly wrapping body 65 is increased by the amount correspondingto the thicknesses produced when the foam resin sheets 53 a, 53 b, 53 cand 53 d attached to the film sheet 57 can be contracted.

The heat radiation sheet 66 a is attached to the surface of the top 62of the outer casing 54 as has been described before with reference toFIG. 8. FIG. 12C is a schematic diagram showing a portion D in FIG. 12Bin an enlarged-scale. As shown in FIG. 12C, a far-infrared raytransmitting and receiving member made of ceramic for radiating orabsorbing far-infrared rays, for example, manufactured by OKI ELECTRICINDUSTRY COMPANY LIMITED under the trade name of “MAZUHARU ICHIBAN”(registered trademark) can be used as this heat radiation sheet 66 aformed on a bonding sheet 67 comprising the bonding layer. Although ahard type far-infrared ray transmitting and receiving member in whichceramic is coated on a base such as aluminum or a far-infrared raytransmitting and receiving member using a flexible film as a basethereof is commercially available on the market, the present inventionis not limited thereto and a far-infrared ray transmitting and receivingmaterial such as ceramic may be directly coated on the outer surface ofthe top 62 of the outer casing 54 or the inner surface of the cover 24.Also, the outer casing 54 may be processed as a box from a metalmaterial such as aluminum coated with the far-infrared ray transmittingand receiving member.

Accordingly, when the sub-assembly wrapping body 65 is pushed into theouter casing 54 with pressure as shown by an open arrow C in FIG. 12B,the foam resin sheets 53 b, 53 c and 53 d attached to the film sheet 57are crushed and the surface of the film sheet 57 is slippery so that thesub-assembly wrapping body 65 can be smoothly inserted into the outercasing 54.

The sub-assembly wrapping body 65 incorporating therein the HDD 45inserted into the outer casing 54 can be strongly held within the outercasing 54 by the swollen (expanded) foam resin sheets 53 b, 53 c and 53d. A method of removing the sub-assembly wrapping body 65 inserted intothe outer casing 54 as described above from the outer casing 54 withease will be described with reference to FIGS. 13A, 13B and FIG. 14.

In FIGS. 13A, 13B and FIG. 14, FIGS. 13A and 13B are perspective viewsshowing, in a partly cross-sectional fashion, the state in which thesub-assembly wrapping body 65 is inserted into the outer casing 54, andFIG. 14 is a cross-sectional side view showing the state in which thesub-assembly wrapping body 65 is pulled out of the outer casing 54. Whenthe sub-assembly wrapping body 65 incorporating therein the HDD 45loaded into the outer casing 54 is pulled out of the outer casing 54,since the tongue-like pull-out member 57 g formed on the film sheet 57lies on the side of the back plate 54B of the outer casing 54 as shownin FIG. 13A, a user raises this tongue-like pull-out member 57 g withfingers as shown in FIG. 13B and lifts the pull-out member 57 g as shownby an open arrow E in FIG. 14, whereby the foam resin sheets 53 b, 53 cand 53 d attached to the wrapping body 59 are lifted while they arecontracted by the front plate 54F and the left and right plates 54L,54R. As a result, the user is able to pull out the sub-assembly wrappingbody 65 from the outer casing 54 with ease.

The sub-assembly wrapping body 65 incorporating therein the HDD 45 asdescribed above can be easily inserted into or removed from the outercasing 54 by using slippage on the slippery surface of the film sheet57. While the top 62 of the sub-assembly wrapping body 65 is beingdirected upwards, the sub-assembly wrapping body 65 is fixed to thesub-chassis 47 through the foam resin sheet 53 a by suitable means suchas screws as shown in FIG. 8. Accordingly, as shown in FIG. 8, thesub-assembly wrapping body 65 becomes able to use the foam resin sheet53 a as the shock-absorbing member relative to the sub-chassis 47 sothat the HDD 45 can be insulated from vibrations of the sub-chassis 47.

Next, a method of controlling the first and second cooling fans 32 and35 provided within the chassis 21 of the recorder 20 shown in FIGS. 5and 6 will be described with reference to a flowchart of FIG. 15. TheCPU 34 shown in FIG. 5 executes control operations shown in theflowchart of FIG. 15. The two first and second cooling fans 32 and 35are able to rotate at high speed (hereinafter referred to an “H rotationmode”) and at low speed (hereinafter referred to as an “L rotationmode”) selectively.

Referring to FIG. 15 in detail, and when a power switch is turned on,the CPU 34 starts controlling the two cooling fans 32 and 35. Then,control goes to a first step ST1, whereat the power switches of thefirst and second cooling fans 32 and 35 are turned off by stop setting.In the first step ST1, the first and second cooling fans 32 and 35 areplaced in the stop mode during a predetermined time period of T0(minute), for example, 5 minutes in order to dump a noise since thepower switch has been turned on.

Then, control goes to the next second decision step ST2, whereat it isdetermined by the CPU 34, which has been described with reference toFIG. 5, whether or not a temperature detected by the open air detectionsensor 38 is higher than a predetermined temperature T1° C. (forexample, 55° C.). If the temperature detected by the open air detectionsensor 38 is higher than the predetermined temperature T1° C., then itis determined that the open air detection sensor 38 is de-energized.Thus, if the detected temperature is higher than the predeterminedtemperature T1° C. as represented by a YES at the second decision stepST2, then control goes to a 14th step ST14, whereat the CPU 34 executesemergency processing to de-energize the recorder 20. In the emergencyprocessing at the 14th step ST14, the power switch of the power supplyunit 27 is turned off and the power switch can be prevented from beingturned off even when the power supply unit 27 is again energized so longas the emergency processing is canceled. If the temperature detected bythe open air detection sensor 38 is lower than the predeterminedtemperature T1° C. as represented by a NO at the second decision stepST2, then control goes to a third decision step ST3.

It is determined by the CPU 34 at the third detection step ST3 whetheror not a temperature detected by the open air detection sensor 38 ishigher than a predetermined temperature T2° C. (for example, 35° C.). Ifthe temperature detected by the open air detection sensor 38 is higherthan the predetermined temperature T2° C. as represented by a YES at thethird detection step ST3, then control goes to a tenth step ST10,whereat the CPU 34 executes high speed rotation setting processing toallow the first and second cooling fans 32 and 35 to rotate at highspeed (H rotation mode). If the detected temperature is not higher thanthe predetermined temperature T2° C. as represented by a NO at the thirddecision step ST3, then the two cooling fans 32 and 35 are de-energizedrespectively. More specifically, if the temperature detected by the openair detection sensor 38 is not higher than the predetermined temperatureT2° C. as represented by a NO at the third decision step ST3, thencontrol goes to a fourth decision step ST4. In the fourth decision stepST4, it is determined by the CPU 34 whether or not a temperaturedetected by the CPU sensor 39 added to the CPU 34 is higher than apredetermined temperature T3° C. (for example, 60° C.). If thetemperature detected by the CPU sensor 39 is higher than thepredetermined temperature T3° C. as represented by a YES at the fourthdecision step ST4, then control goes to the tenth step ST10, whereat theCPU 34 executes high speed rotation setting processing to allow thefirst and second cooling fans 32 and 35 to rotate at high speed (Hrotation mode). If on the other hand the detected temperature is nothigher than the predetermined temperature T3° C. as represented by a NOat the decision step ST4, then control goes to a fifth decision stepST5.

It is determined at the fifth decision step ST5 by the CPU 34 whether ornot the predetermined time T0 (for example, 5 minutes) passed. If thepredetermined time T0 does not pass as represented by a NO at the fifthdecision step ST5, then control goes back to the second decision stepST2. If on the other hand the predetermined time T0 passed asrepresented by a YES at the fifth decision step ST5, then control goesto a sixth step ST6.

In the sixth step ST6, the CPU 34 sets the first and second cooling fans32 and 35 to the L rotation state, respectively so that the first andsecond cooling fans 32 and 35 can be rotated at low speed.

Then, control goes to a seventh decision step ST7, whereat it isdetermined by the CPU 34 whether or not a temperature detected by theopen air detection sensor 38 is higher than the predeterminedtemperature T1° C. If the detected temperature is higher than thepredetermined temperature T1° C. as represented by a YES at the 7thdecision step ST7, then the open air detection sensor 38 is de-energizedand control goes to the 14th step ST14, whereat the CPU 34 executes theemergency processing to turn off the power supply. If on the other handthe detected temperature is not higher than the predeterminedtemperature T1° C. as represented by a NO at the 7th decision step ST7,then control goes to the next 8th step ST8.

It is determined at the 8th decision step ST8 by the CPU 34 whether ornot a temperature detected by the open air detection sensor 38 is higherthan the predetermined temperature T2° C. If the detected temperature ishigher than the predetermined temperature T2° C. as represented by a YESat the 8th decision step ST8, then control goes to the 10th step ST10,whereat the first and second cooling fans 32 and 35 are switched to theH rotation state, that is, the first and second cooling fans 32 and 35can rotate at high speed. If on the other hand the detected temperatureis not higher than the predetermined temperature T2° C. as representedby NO at the 8th decision step ST8, then control goes to the next 9thdecision step ST9. It is determined at the 9th decision step ST9 by theCPU 34 whether or not a temperature detected by the CPU sensor 39 ishigher than the predetermined temperature T3° C. If the detectedtemperature is higher than the predetermined temperature T3° C. asrepresented by a YES at the 9th decision step ST9, then control goes tothe 10th step ST10, whereat the first and second cooling fans 32 and 35are switched to the H rotation mode, that is, the first and secondcooling fans 32 and 35 can rotate at high speed. If on the other handthe detected temperature is not higher than the predeterminedtemperature T3° C., then control goes back to the 7th step ST7, and the7th decision step ST7 to the 9th decision step ST9 are repeated.

In the 10th step ST10, the first and second cooling fans 32 and 35 arerotated at high speed in the H rotation mode as described above. Controlgoes to the next 11th decision step ST11, whereat it is determined bythe CPU 34 whether or not a temperature detected by the open airdetection sensor 38 is higher than the predetermined temperature T1° C.If the detected temperature is higher than the predetermined temperatureT1° C. as represented by a YES at the 11th decision step ST11, then theopen air detection sensor 38 is de-energized and control goes to the14th step ST14, whereat the CPU 34 executes the emergency processing tode-energize the power supply. If the detected temperature is not higherthan the predetermined temperature T1° C. as represented by a NO at the11th decision step ST11, then control goes to the next 12th decisionstep ST12. It is determined at the 12th decision step ST12 by the CPU 34whether or not a temperature detected by the open air detection sensor38 is higher than a predetermined temperature T4° C. (for example, 32°C.).

If the detected temperature is higher than the predetermined temperatureT4° C. as represented by a YES at the 12th decision step ST12, thencontrol goes back to the sixth step ST6, whereat the first and secondcooling fans 32 and 35 are rotated at low speed (L rotation mode). If onthe other hand the detected temperature is not higher than thepredetermined temperature T4° C. as represented by a NO at the 12thdecision step ST12, then control goes to the next 13th decision stepST13. It is determined at the 13th decision step ST13 by the CPU 34whether or not a temperature detected by the CPU sensor 39 is lower thana predetermined temperature T5° C. If the detected temperature is higherthan the predetermined temperature T5° C. as represented by a NO at the13th decision step ST13, then control goes back to the 11th decisionstep ST11 and the 11th decision step ST11 to the 13th decision step ST13are repeated. If the detected temperature is lower than thepredetermined temperature T5° C. as represented by a YES at the 13thdecision step ST13, then control goes back to the sixth step ST6,whereat the first and second cooling fans 32 and 35 are both rotated atlow speed (L rotation mode).

Specifically, according to the present invention, when the power supplyis set to the initial state, the two first and second cooling fans 32and 35 are placed in the de-energized state for about 5 minutes in orderto dump a noise. If the temperature detected by the open air detectionsensor 38 is lower than the predetermined temperature T1° C., then thefirst and second cooling fans 32 and 35 are placed in the de-energizedstate. If on the other hand the above temperature detected by the openair detection sensor 38 is higher than the predetermined temperature T1°C., then the first and second cooling fans 32 and 35 are rotated at highspeed (H rotation mode). If the temperature detected by the open airdetection sensor 38 is lower than the predetermined temperature T1° C.and a predetermined time T0 (5 minutes) passed, then the first andsecond cooling fans 32 and 35 are rotated at low speed (L rotationmode). If the temperature detected by the open air detection sensor 38becomes higher than the predetermined temperature T2° C. and the openair detection sensor 38 is de-energized, then control of the CPU 34 goesto the emergency processing to de-energize the power supply. If thetemperature detected by the CPU sensor 39 becomes higher than thepredetermined temperature T3° C., then the first and second cooling fans32 and 35 are rotated at high speed (H rotation mode).

Also, if the temperature detected by the open air detection sensor 38becomes higher than the predetermined temperature T1° C., then the firstand second cooling fans 32 and 35 are rotated at high speed (H rotationmode). If the temperature detected by the open air detection sensor 38becomes higher than the predetermined temperature T2° C. and the openair detection sensor 38 is de-energized, then control of the CPU 34 goesto the emergency processing at the step ST14 to de-energize the powersupply. If the temperature detected by the CPU sensor 39 becomes higherthan the predetermined temperature T3° C., then the first and secondcooling fans 32 and 35 are rotated at high speed (H rotation mode).

Further, if the temperature detected by the open air detection sensor 38becomes lower than the predetermined temperature T4° C., then the firstand second cooling fans 32 and 35 are rotated at low speed (L rotationmode). If on the other hand the temperature detected by the open airdetection sensor 38 becomes higher than the predetermined temperatureT1° C. and the open air detection sensor 38 is de-energized, thencontrol of the CPU 34 goes to the emergency processing at the step ST14to de-energize the power supply. If the temperature detected by the CPUsensor 39 becomes lower than the predetermined temperature T5° C., thenthe first and second cooling fans 32 and 35 are rotated at low speed (Lrotation mode).

According to the present invention, in the electronic apparatus in whicha signal is recorded and/or reproduced by the hard disk drive and inwhich heat generated from the hard disk drive is transmitted to the heattransmission unit and introduced into the heat radiation unit andthereby radiated to the outside, the hard disk drive is attached to thefixed portion of the electronic apparatus through an elastic materialand the heat radiation unit is attached to the fixed portion of theelectronic apparatus without an elastic material. Also, the hard diskdrive, the heat radiation unit and the heat transmission unit havefar-infrared transmitting and receiving members formed on their surfacesso that heat is transmitted through two opposing surfaces distant fromeach other by a predetermined length. Thus, it is customary that the HDDis attached to the fixed portion such as the base of the electronicapparatus through the elastic material so that the HDD may be preventedfrom being directly shocked by vibrations. On the other hand, when theheat radiation unit is directly attached to the base, there is anadvantage that heat is transmitted from the heat radiation unit to thebase. However, when the heat radiation unit and the HDD are joined bymeans of a heat transmission member, vibration and shock of the fixedportion are directly transmitted to the HDD. Therefore, according to thearrangement of the present invention, that is, “heat is transmittedthrough the two opposing surfaces distant from each other by thepredetermined length in which the far-infrared ray transmitting andreceiving members are disposed”, there can be constructed an arrangementin which vibration and shock can be prevented from being transmitted tothe hard disk drive although heat can be transmitted thereto.

A first embodiment according to the present invention will be describedbelow.

In the sub-assembly wrapping body 65 that has been described so far withreference to FIG. 8, heat accumulated in the inner casing 50 of the HDD45 is transmitted to the outer casing 54 through the heat conductivesheet 55. As shown in FIG. 16A, the far-infrared ray transmitting andreceiving members composed of the heat radiation sheets 70 a, 70 bhaving arrangements similar to those of the heat radiation sheets 66 a,66 b (see FIG. 8) are located at the opposing distant positions of thetop 60 of the inner casing 50 of the HDD 45 and the top 62 of the outercasing 54 to thereby transmit accumulated heat from the top 60 of theinner casing 50 of the HDD 45 to the heat radiation sheet 70 b. Radiatedheat is absorbed by the heat radiation sheet 70 a disposed on the innersurface of the top 62 of the outer casing 54, and heat radiated to theouter casing 54 is radiated from the cover 24 through the far-infraredray transmitting and receiving members composed of the heat radiationsheet 66 b and the heat radiation sheet 66 a disposed on the cover 24.In FIGS. 16A and 16B, elements and parts identical to those of FIG. 8are denoted by identical reference numerals and therefore need not bedescribed.

FIG. 16B shows a further arrangement of the present invention. As shownin FIG. 16B, the heat radiation sheets 70 a, 70 b similar to those ofFIGS. 8 and 16A are used to radiate heat accumulated in the HDD 45 tothe heat sink 73 provided on the sub-chassis 47.

As shown in FIG. 16B, the HDD 45 has the vibration isolating structurerelative to the sub-chassis 47 by the shock absorbing device such as therubber leg portions 73, and the inner wall of the outer casing 45 iscovered with the foam resin sheet 53 to thereby dump a noise and toisolate a noise. A metal heat transmission plate 72 of a substantiallysquare shape is located at the position at which it is distant from theceramic heat radiation plate 70 b formed on the top 60 of the HDD 45 inan opposing fashion. A far-infrared ray transmitting and receivingmember formed of the heat radiation sheet 70 a is attached to theposition at which the heat transmission plate 72 and the heat radiationsheet 70 b are opposed to each other. One end of the heat transmissionplate 72 is fixed to the opposite side of the fins of the heat sink 71and it is projected from the through-hole 74 bored on the outer casing54. Accordingly, heat from the HDD 45 is radiated from the heatradiation sheet 70 b to the space, it is absorbed by the heat radiationsheet 70 a of the heat transmission plate 72, it is transmitted to theheat transmission plate 72 and it is further radiated through the heattransmission plate 72 from the heat sink 71 to the air.

According to the HDD 45 having the arrangement shown in FIGS. 16A and16B, since accumulated heat from the HDD 45 or the outer casing 54 iscompletely isolated from the cover 24 serving as the heat radiation bodyand the heat sink 71, even when shocks and vibrations are applied tothese heat radiation bodies, shocks and vibrations can be prevented frombeing transmitted to the HDD 45 and hence the HDD 45 can become morereliable.

A second embodiment of the present invention will be described below.

An example of other arrangement of the film sheet 57 that has beendescribed so far with reference to FIG. 10 will be described withreference to FIG. 17. In FIG. 17, elements and parts identical to thoseof FIG. 10 are denoted by identical reference numerals and thereforeneed not be described. In the arrangement shown in FIG. 17, dome-liketongue portions 76L, 76R, 76F and square folding members 77 serving asthe fastening margins of the front and back folding sheet members 57F,57B are formed on the left folding sheet member 57L, the right foldingsheet member 57R and the front folding sheet member 57F of the filmsheet 57. Upon assembly, the tongue portions 76L, 76R, 76F are insertedinto groove holes 78 formed on the lower sheet 57 b, and in the state inwhich the wrapping body 59 or the sub-assembly wrapping body 65 isassembled, the film sheet 57 can be formed as an inner box type.According to this arrangement, the sub-assembly wrapping body 65 can bemounted on the outer casing 54 more easily.

While the recorder including the HDD or the DVD has been described sofar as the above-described electronic apparatus, the present inventionis not limited thereto and the present invention can be applied tovarious kinds of apparatuses and electronic apparatuses, which generateheat, such as a disk recording and reproducing apparatus for recordingand reproducing disks such as a CD (compact disc) and a CD-ROM (CD-readonly memory) and recording and reproducing apparatus using a tape as arecording medium such as a VTR (video tape recorder) and a taperecorder.

According to the above-mentioned HDD and electronic apparatus of thepresent invention, there can be obtained the HDD and the electronicapparatus in which the HDD can be protected from being shocked when theshock is applied the electronic apparatus and the heat radiation meansof the HDD from the outside.

According to the electronic apparatus and the HDD of the presentinvention, there can be obtained the electronic apparatus and the HDD inwhich heat generated from the HDD can be efficiently radiated and a seeknoise generated when the pickup head within the HDD frequently seeks atarget track can be decreased so that reliability of hard disk functioncan be maintained.

Having described preferred embodiments of the invention with referenceto the accompanying drawings, it is to be understood that the inventionis not limited to those precise embodiments and that various changes andmodifications could be effected therein by one skilled in the artwithout departing from the spirit or scope of the invention as definedin the appended claims.

1. An electronic apparatus comprising: a hard disk drive for recordingand/or reproducing a signal; a heat transmission portion for receivingheat generated from said hard disk drive and transmitting received heat;a heat radiation portion for radiating heat transmitted from said heattransmission portion; and an arrangement in which said hard disk driveis attached to a fixed portion of said electronic apparatus through anelastic material, said heat radiation portion is attached to said fixedportion of said electronic apparatus without said elastic material andheat is transmitted to said hard disk drive, said heat radiation portionand said heat transmission portion through two opposing surfaces of afar-infrared ray transmitting and receiving member are separated fromeach other by a predetermined distance.
 2. The electronic apparatusaccording to claim 1, wherein said electronic apparatus comprises: abox-shaped outer casing in which an inner casing of said hard disk driveis housed through one of a noise insulation member and a vibrationisolation member; a chassis for holding said outer casing by ashock-absorbing member; and a cover for covering said chassis, whereinheat from said inner casing of said hard disk drive is transmitted tosaid box-shaped outer casing and the transmitted heat is radiatedthrough said far-infrared ray transmitting and receiving member disposedon the outer surface of said outer casing to said cover with or withoutsaid far-infrared ray transmitting and receiving member being disposedthereon.
 3. The electronic apparatus according to claim 1 or 2, whereinsaid far-infrared ray transmitting and receiving member is one of aceramic sheet and a ceramic paint.
 4. The electronic apparatus accordingto any one of claims 1 to 3, wherein said heat transmission portion isone of a foam heat transmission sheet or and far-infrared ray radiationmember.
 5. A hard disk drive housing apparatus comprising: a box-shapedouter casing in which a hard disk drive is housed through one of a noiseinsulation member and a vibration isolation member; a chassis forholding said box-shaped outer casing by a shock-absorbing member; acover for covering said chassis; a heat transmission portion disposed ona top of said inner casing of said hard disk drive housing apparatus; afar-infrared ray transmitting and receiving member disposed on an outersurface of said box-shaped outer casing; and a heat radiation portionwith or without said far-infrared ray transmitting and receiving memberdisposed at a position opposing to and spaced apart from the outersurface of said box-shaped outer casing, wherein heat of said innercasing is transmitted to said box-shaped outer casing through said heattransmission portion and heat within said inner casing is radiated tosaid heat radiation portion.
 6. The hard disk drive housing apparatusaccording to claim 5, wherein said far-infrared ray transmitting andreceiving member is one of a ceramic sheet a ceramic paint.